Rotary transfer cylinder interrupter responsive to varying cylinder speeds



Feb. 1966 c. L. HORNBERGER ETAL 3,234,374

ROTARY TRANSFER CYLINDER INTERRUPTEH RESPONSIVE TO VARYING CYLINDER SPEEDS 4 Sheets-Sheet 1 Filed April 5, .1963

1966 c. L. HORNBERGER ETAL 3,234,374

ROTARY TRANSFER CYLINDER INTERRUPIER RESPONSIVE TO VARYING CYLINDER SPEEDS Filed April 5, 1963 4 Sheets-Sheet 2 *flww 4/ F162. 22 26 44 80 FIG. 3.

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FDWA/QD. 14/. STANLEY 3,234,874 YLINDER INTERRUPTER HESPONSIV 1956 c. L. HORNBERGER ETAL ROTARY TRANSFER C TO VARYING CYLINDER SPEEDS 4 Sheets-Sheet 4 Filed April 5, 1963 EDWARD 14/. STANLEY United States Patent Ofifice 3,234,874 Patented Feb. 15, 1966 ROTARY TRANSFER CYLINDER INTERRUPTER RESPONSIVE T VARYING CYLINDER SPEEDS Clarence L. Hornberger and Edward W. Stanley, Lancaster, Pa., assignors to Armstrong Cork Company,

Lancaster, Pa., a corporation of Pennsylvania Filed Apr. 5, 1963, Ser. No. 270,918 6 Claims. (Cl. 101-218) This invention relates to apparatus and method for articulating printing press rolls at varying speeds, and has for an object the provision of improvements in this art.

The invention relates particularly to the operation and control of a rotogravure printing press of the type disclosed in the copending application of the present applicants and others, Ser. No. 134,606, filed Aug. 29, 1961, now Patent No. 3,099,956, and assigned to a common assignee. The invention relates more particularly to cross border skip printing apparatus and method disclosed in the copending application of the present applicants, Ser. No. 270,870, filed April 5, 1963, assigned to a common assignee.

In the earlier application referred to there is disclosed a rotogravure press line comprising a number of press stands for successively printing on a web which travels serially through the press stands. The application also discloses details of mechanism of a single press roll stand formoving or articulating an offset roll relative to the associated engraved and impression rolls. This mechanism includes a cradle mounted on pivots at each end near the roll nips and supporting the offset roll for movement by a hydraulic power cylinder.

In the later application referred to there is disclosed a method and means for positively operating both ends of the cradle for cross border skip printing for variable skip lengths controlled by selectively settable movement unit counters for different hydraulic motors which separately operate the opposite ends of the cradle for inking and printing actions.

In any of these systems the mechanical devices employed to articulate the rolls require an appreciable time to perform their actions. Even when the length of stroke is reduced to a minimum to reduce the operating time, as described in the second-mentioned application, the time required is very appreciable.

If the rolls were run at a constant speed the timing for the roll shifting means relative to the roll speed could be established permanently for correct operation.

Correct operation, in the sense here discussed, means that the rolls must be separated at a precise point in their rotation and must be returned as precisely in order to stop and start inking and printing, as for cross borders, in the correct locations; for while all rolls are caused to rotate at exactly the same speed at all times, whether engaged or disengaged, it will be clear that the rotative points of separation and re-engagement will be controlled by the factors of roll speed and articulation speed.

It is, therefore, an object of the present invention to provide means and method for compensating for different roll speeds in relation to the articulation of the rolls of a roll stand.

Another object is to provide means for automatically adjusting the registry points of articulation with the adjustment of the speed of the press.

The above and other objects of the invention, as well as various novel features and advantages, will be apparent from the following description of an exemplary embodiment thereof, reference being made to the accompanying drawings, wherein:

FIG. 1 is an end elevation of a roll stand embodying the present invention;

FIG. 2 is a schematic operating diagram showing one stage of the articulating action;

FIG. 3 is a view like FIG. 2 but showing the parts in a different stage of operation;

FIG. 4 is a view like FIG. 2 but showing the parts in an inking stage;

FIG. 5 is a schematic diagram showing an. arrangement for printing cross borders where two cross borders can be formed at one complete revolution of the rolls;

FIG. 6 is a diagram of a timing signal plate.

The roll stand, as shown in F161, comprises an engraved or plate roll 20, an offset or blanket roll 21 and a web-supporting impression roll 22. The engraved roll and the impression roll are mounted in a fixed position, although all rolls can readily be freed for lifting out by a crane; and the offset roll is articulated or mounted for movement toward and from the engraved and impression rolls.

The engraved roll is provided with journals or trunnions 23 at its ends, one being shown, supported in bear ings 24 of the main roll stand frame 25. Suitable means, not shown, are provided for coating the engraved surface with ink and removing the excess, as explained in the earlier copending application referred to.

The impression roll 22 has journals or trunnions 26 mounted in bearings 27. The bearing 27 at each end, for reasons fully explained in the copending application, is mounted on an arm 23 pivoted at its lower end on the main frame at a journal 29 and adjusted at the upper end, as by a pin 30 movable in a slot 31 of a member 32, the pin being moved by the cam surface 33 of a cam arm 34 turnably mounted on a fixed pivot shaft 35.

The web W which is to be imprinted passes up over the impression roll 22, being fed up from below over a tension adjusting roll 37 mounted on an arm 38 pivoted at 39 and adjusted by a fluid power device 40.

At each end the offset roll 21 has a journal! or trunnion 41 supported in a bearing 42 and a bearing is supported on a cradle 43 for various controlled movements with which the present invention is especially concerned.

At one end, the left in FIG. 1, the cradle 43 is mounted on a pivot shaft 44 carried by an arm 45 which is turnably mounted on the same pivot shaft as thecam arm 34.

The arm also carriers a bearing 46 for the journal 47 of a blotter roll 48, a slot 49 being provided in the main frame to accommodate the journal movements.

Means are provided for moving the arm 45 for turning movement about the axis of the shaft 35, the means here provided being a fluid motor 56 comprising a cylinder, designated by the same number, pivoted on a hinge pin 51 carried by a fixed mount 52 and having a piston rod 53 connected to the arm 45 by a pivot pin 54.

From a consideration of the parts thus far described, it may be seen that when the power device acts on the arm 45 it will turn it about its hinge point, i.e., the axis of the shaft 35, and this movement will cause the pivot shaft 44 at one end of the cradle 43 to be translated to describe an are about the axis of shaft 35. This movement of the cradle will separate the offset roll 21 from the impression roll 22 and tend to pull the offset roll away from the engraved roll 20.

The other end of the cradle 43 is bifurcated or slotted so as to have an upper finger 55 and a lower finger 56 embracing the upper and lower flat sides of a guide sleeve, bushing, or shoe 57 which is turnably mounted on an eccentric pin 58 of an eccentric shaft 59 mounted in the main frame.

The sleeve or shoe 57 may be moved up or down by moving the eccentric pin 58 up or down and this may be done by turning the eccentric shaft 59 in its bearings. For this purpose the shaft 59 is provided with an arm 60 adapted to be turned by suitable adjusting means.

The means for turning the eccentric shaft arm 60 to set for different adjusted positions of the offset roll 21 against the engraved roll 28 comprises a bellcrank lever 65 turnably mounted on a stud shaft 66 secured on the main frame. One arm 65a of the bellcrank lever 65 is provided with a pin-and-slot connection, designated as 67, with the end of the eccentric arm 60 and the other arm 65]) is provided with a pivot connection 68 for an adjusting rod 69 which is moved and set in different positions by means which are fully described in the copending application.

Means are provided for limiting the upward movement of the arm 45 carrying the cradle pivot 44, the means here shown comprising an adjustable stop element in the form of a lockable set screw 70, carried by an extension 45a of the arm 45, which engages some convenient fixed stop abutment, such for example, as a sleeve 71 mounted on the stub shaft 66.

Adjustable means are provided for limiting the downward movement of the arm 45, the means here shown comprising a lever 73 mounted on the stub shaft 66, the lever having an arm 73a carrying a stop abutment surface 74- adapted to be engaged by a lockable set screw 75 carried by a projection 45b of the arm 45. The other arm 73b of the lever 73 is provided with a pivot connection 76 for an adjusting rod '77 which is adjusted by suitable means, as fully described in the copending application.

The organization as thus far described is that of the first copending application. Initially, in the interest of shorter and faster movement of the offset roll to accommodate for higher press roll speeds, the adjustment screw 70 is made longer to limit the outward movement of the offset roll. In the original arrangement the movement was such as to provide a separation of about at the nip IO between the impression and offset rolls and a separation of about 4 at the nip EO between the engraved and ofiset rolls. By adjustment of the screw 7% the opening in the impression offset nip IO can be cut down to about 71 while still providing separation at the engraved-offset nip E-O of about & which is about the minimum safe operating space at the nip EO. This is achieved solely by movement of the cradle pivot 44 by turning the arm 45 by the power motor f).

This reduced movement of articulation contributes to smoother operation, less impact against stops, less wear in the roll shaft coupling and less time for action. The total time for articulating the offset cylinder is fixed as a function of response of the various components and does not vary with press speeds. Hence for increased press speeds and shorter spacings between cross borders which are desired, the present invention makes a number of modifications to the existing equipment, as will now be described.

While these improvements are provided for the desired special purposes, they are designed to be fully compatible with the existing equipment and of such a nature that there may be a quick selective reversion to the original type of operation.

As a first departure, it is arranged that the offset roll 21 may be separately and independently articulated relative to the engraved roll 28. This is done by providing separate means for moving the other (right hand) and of the cradle 43 up and down.

To permit of this independent movement of the righthand end of the cradle 43, a clearance space is provided between the lower finger 56 of the cradle and the bottom surface of the guide sleeve or shoe 57. For a concrete example, this bottom clearance or lost motion space may be about /2".

The lower finger 56 is provided with a projection 56a and to this projection there is secured, as by a pivot pin 8ft, an operating link 81, the link at its lower end being connected, as by a pivot pin 82, to an arm 33a of a bellcrank lever 83 turnably mounted on a fixed pivot pin 84 carried by the main frame.

The other arm 83b of the bellcrank lever 83 is connected by a pivot pin 85 to a clevis member 86 adjustably secured, as by screw threads, to the end of a piston rod 87 of an auxiliary fluid power motor 88. The cylinder of the motor 88, designated by the same number 88, is turnably secured to the main frame by a pivot pin 89.

It is arranged, by the adjustable clevis member 86, that the upper finger 55 always comes to rest on the top surface of the shoe 5'7; that is, the piston in the cylinder 88 never bottoms on the instroke (toward the head end) but always bottoms on the outstroke (toward the rod end), the point of stoppage and the extent of lift of the right end of the cradle 43 being established by the adjustment of the clevis 86.

The relationships are such that by action of the auxiliary fluid motor 88 alone, and without any action by the main or primary motor 50, the offset roll 21 may be moved or articulated relative to the engraved roll 21 to open the space E-O between the rolls by about ,4 Movement of the cradle 43 about the pivot point 44 does not change the contact relationship between the offset and impression rolls at the nip IO because the pivot point 44 is located very near the nip. For a similar reason, very limited turning of the cradle 43 about the pivot point of the axis of the eccentric pin 58 does not change the relationship between the engraved and offset rolls at the nip E-O because the axis of pin 58 is located very near the nip between these rolls. It is only the swinging movement of the point 44 about the remote axis 35 that, in continued movement, causes the finger 55 to slide back on the shoe 57 and the offset roll to pull away from the engraved roll.

FIG. 2 shows additional auxiliary equipment which has been provided. Here, as in other views, only one end of the rolls is shown but it will be understood that the other end of the offset roll is moved by duplicate means provided there so as to exactly match the movements at the end which is shown.

There is an auxiliary cylinder 92 having a piston 93 therein with a rod 94 of appreciable size to make a significant difference in effective area between the head end and the rod end. An adjustable stop collar 95 is provided on the rod 94- to limit its inward movement and thereby to limit the length and capacity of the cylinder space on the rod end side of the piston.

In effect the cylinder 92 acts to shorten the stroke of the piston of the main power motor SO much like the action obtainable by adjusting the screw 70 but secures the change in action automatically without requiring stoppage of operations as would be required to re-set the screw 70.

A flow reversing control valve 96, operated by a solenoid 97, is provided for the main power cylinder 50; and a flow reversing control valve 98, operated by a solenoid 99, is provided for the auxiliary power cylinder 88.

The auxiliary cylinder 92 is interposed in the rod-end fiuid line of the main power cylinder 50, a fluid line 161 being provided between the head end of the cylinder 92 and the reversing valve 96. Between the fluid lines 100 and 101 there are provided a spring-loaded check valve 102 opening toward line 100 and a cut-off valve 103 operated by a solenoid 104.

A fluid line 105 connects the head end of the main power cylinder 50 with the reversing valve 96. Fluid lines 106 and 107 connect the head end and rod end, respectively, of the auxiliary power cylinder 88 with the reversing valve 98.

A press run switch S1 is provided to control the entire sub-circuit here shown, this switch directly controlling the solenoid 104 of the valve 103 so as to move it from its normally open position and close it. A switch S2, which is normally open for regular printing, may be closed by a selective gang operator 110 when border printing is desired.

The switch S2 is in series with the switch S1 and an :3 inking control counter switch S3 in a line to the solenoid 99 of the reversing valve 98 which controls the auxiliary fluid motor 88. The switch S3 is controlled by a counter which is tied in with the rotation of the offset roll 21 and controls the engagement of the offset roll with the engraved roll for transferring an engraved ink impression from the engraved roll to the offset roll. The operation of the counter and this switch will be described presently.

The gang control selector operator 110 also moves a common contact plate for a regular switch S4 and a border print switch S5 in a line from the switch S1 to the solenoid 97 of the reversing valve 96 for the main power motor 50. A switch S6 is in series with the switch S5 and is operated by a counter which controls printing, that is, the engagement of the offset roll 21 with the web on the impression roll 22. This counter will also be described presently.

FIG. 5 shows an arrangement in which the offset roll 21 is provided with two segment pads A and B and the engraved roll is provided with matching engraved portions A and B. The shaft of the offset roll 21 drives a timing disk 118, either directly or through a chain 119 and suitable sprockets. For the front and rear ends of the pads A and B, the disk 118 is provided with an inner circular set of ink signal openings A-I-l, A-I-2, B-I1, B-I-Z for controlling inking by a signal inputoutput device 120 and also is provided with an outer circular set of signal print openings AP1, AP2, B-P1, B-P-2 for controlling printing by a signal inputoutput device 121. The device 120 is connected with an inking timing counter 122 and the device 121 is connected with a printing timing counter 123.

OPERATION A. Regular printing-Switch S1 is closed when the roll stand becomes active for printing. The gang operator 110 is in the regular position.

As soon as switch S1 closes, the solenoid 104 of valve 103 is energized and the valve 103 is closed. It remains closed as long as switch S1 remains closed.

The solenoid 99 for the valve 98 of the auxilary motor 855 is tie-energized (because of the gap at S2) and fluid pressure is imposed on the rod end of the cylinder to keep the right hand end of the offset roll cradle 43 in its lower position.

Switch S4 is in closed position to energize the solenoid 97 of valve 96 for the main motor 50. Pressure fluid flows to the rod end of the main power cylinder 50 and lowers the piston and, with it the offset roll 21, into contact with the other rolls, fluid flowing from the head end of the cylinder directly to tank T.

The cylinder device 92 has no effect for the following reason: pressure fluid flows from the valve 96 to the line 101 and flows through the check valve 102 and line 100 to the cylinder 50. Assume that the check valve opens at a pressure of 65 p.s.i. This means that fluid pressure from valve 96 is exerted on both sides of the piston in the cylinder 92; but the pressure on the head end is greater than on the rod end by the amount of 65 psi, valve 103 being closed; and there is no action by the cylinder device 92. I

.The ink switch S3 and the print switch S6 of the counter may operate but they are not in cricuit and will have no effect.

At the end of the run, switch S1 opens and the parts revert to the idling position with the offset cylinder held clear above the engraved and impression cylinders.

It is thus seen that the auxiliary equipment which has been added has no effect on regular printing operations, the power device 50 operating in the usual manner.

B. Border skip printing-Gang switch operator 110 is moved to close switches S2 and S5.

Solenoid 99 of valve 98 will be energized when ink switch S3 is closed-and it is shown in closed position.

Solenoid 97 of valve 96 will be de-energized because print switch S6 is open at this time.

Stage 1, FIG. 3

Valve 103 is closed and will remain closed as long as switch S1 is closed, so this valve may be assumed to remain closed and may be disregarded in all further discussion of skip printing operations.

Valve 98, being shifted by its solenoid 99 which is now energized through S2 and S3, will supply pressure fluid to the head end of cylinder 88 to cause the right end of cradle 43 to be raised.

There has been no action of the controls for cylinder 50, print switch S6 being open, so its piston remains raised.

The offset roll cradle isheld up by both cylinders 50 and 88.

Stage 2, FIG. 2

Print switch S6 closes. Ink switch S3 still closed.

The controls for cylinder 88 have not been affected so cylinder 88 will hold the right end of the cradle 43 in raised position.

Closing of print switch S6, selector switch S5 being held closed, will energize the solenoid 97 of valve 96 to supply pressure fluid to the rod end of cylinder 50, the piston 93 of cylinder 92 moving to the rod end, and lower the left end of the cradle.

This will bring the offset roll against the impression roll but there will be no imprint because the offset roll has not been inked.

Stage 3, FIG. 3

Print switch S6 opens. Ink switch S3 remains closed.

The controls for cylinder 88 have not been affected, hence it will continue to hold the right end of the cradle in raised position.

The opening of S6 de-energizes solenoid 97 and valve 96 returns to normal position.

Pressure fluid from valve 96 flows to the head end of cylinder 50 and raises its piston and the left end of the rocker.

However, fluid flowing from the rod end of cylinder 50 is trapped, insofar as flow to the tank side of valve 96 is concerned, check valve 102 being shut against the return side and valve 103 being closed; so return fluid flows into the rod end of cylinder 92 to move the piston over toward the head end until the stop halts its movement. Fluid is free to flow out from the head end of cylinder 92 to the valve 96 and tank.

This limits the upward movement of the pistonin the cylinder 50 to a position where the left end of the cradle is raised only just enough to clear the offset roll from the impression roll.

The offset roll is now held clear of both the engraved roll and the impression roll.

Stage 4, FIG. 4

Ink switch S3 opens. Print switch S6 remains open.

The result of this is that the right hand end of the cradle is lowered to engage one of the pad segments of the offset roll with an ink-coated engraved segment of the engraved roll to .pick up an ink impression on the segment of the offset roll.

It is here to be noted that there are low spaces or gaps in the rubber covering of the ofiset roll; that the raised segment on the engraved roll will be circumferentially longer than the raised p-ad segment on the offset roll; and that the timing is so arranged that the engraved segment arrives and leaves the nip at a low space between segment pads. This avoids scuffing the raised pad segments on the ofiset roll by the action of engaging the engraved roll. Of course, the ink-coated engraved area of the engraved roll will fall fully on the raised pad segment of the offset roll.

Stage 6, FIG. 3, FIG. 2

The next action, an intermediate stage corresponding to FIG. 3, is that the ink switch S3 closes and the cylinder 88 acts to raise the right-hand end of the cradle; but since the left-hand end is being held up by cylinder 50 there is no action. The offset roll is clear of both other rolls as shown in FIG. 3.

After this, the next action is the closure of print switch S6. This brings the parts to the condition shown in FIG. 2.

The cylinder 50 allows the left end of the cradle to be lowered and the ofiYset roll is brought against the web on the impression roll to make a printing impression on the Web.

The action which occurred is as follows: When solenoid 97 was energized and valve 96 reversed, fluid from the head end of cylinder 50 could flow directly to tank, Pressure fluid from the valve 96 was admitted to line M51 and acted on the head end of cylinder 92 to force the piston back to the rod end and force fluid therefrom back into the rod end of cylinder 50 to force the piston down. If needed, more fluid could flow through the check valve 1% from the line 161.

Continued border printing Thereafter, as the ink and print counters alternately close and open at the predetermined count for which the counters 122 and 123 are set, the positions of FIGS. 2, 3, and 4 will be repeated in the order FIG. 4 (ink), FIG. 3 (clear), FIG. 2 (print), FIG. 3 (clear), FIG. 4 (ink), and so on.

The printing action always follows promptly after the inking action even when there is a long count or skip for long rugs between printing actions.

It is contemplated that the counters 122 and 123 will be of a type known on the market as Vee'der-Root counters, or the equivalent, which operate the switch at the high count for which the counter is selectively set and then drop back to zero and shift the switch at the count of one (1) on the next upcount. The counters shown indicate a capacity of a maximum count of twenty (20) and since there is a count of four (4) for each revolution of the offset roll (A-1start of segment A; A2 end of segment A; BIistart of segment B; and B2end of segment B) the counters will accommodate for a skip length of five (5) revolutions or a web length of twentytwo and one-half (22 /2) feet.

It may be well to note here that the ink counter is always initially set up two units in advance of the print counter to be sure that a pad always passes the inking nip before it reaches the printing nip.

The signal input-output devices may be of various known types, such as sonic-electric, photo-electric, and the like. The ink switch S3 will be actuated by the ink counter 122 and the print switch S6 will be actuated by the print counter 123.

FIG. 6 is a disk face diagram to illustrate the positions of the holes or slots in the disks relative to the segment pads on the offset roll and the nominal positions of the beams (of light, sound, etc.) through the holes for a representative speed of the rolls and a minimum travel of the ends of the cradle. Necessarily, the pressure of the fluid used in the cylinders 50 and 88 Will affect the speed of action. By making the travel distance very short the pressure and impact can be minimized while still realizing very fast action by the shortened travel distance. The apparatus as so far described is disclosed in the copending applications referred to.

The means provided by the present invention for making changes in the signal transmission time from the counters to the articulating mechanism in conjunction with changes in press speed is shown in FIGS. 5 and 6. Here it may be seen that the signal-producing devices 12$ and 121 which cooperate with the timing slot holes in the disk 118 are both mounted upon a turnable support or rocker 125 which is mounted for turning movement about the same axis as that on which the disk 118 turns.

The turnable support is provided with a rocker arm 126 by which it may be turned when making speed compensating adjustments.

An adjusting link 127 is connected to the arm 126 by a pivot pin 128 and at its other end the link 127 is connected to an operating arm 12% of gear reducing operating mechanism 130, as by a pivot pin 131 in a slot 132 of the arm 1259. The slot is concentric about the pivot pin 1.23 at the other end of the link and provides means for making an initial setting to secure the optimum coordinated lengths of movements of parts.

A master speed control unit 133 for the press unit (or press line, it may be) may function through a small speed control motor 134 to operate a control device, such as a rheostat 135, to control the main press drive motor 136.

The means for adjusting the articulating means in coordination with the main speed control means comprises a small motor 137 which is controlled, along with the motor 134 for the main speed controls, to operate the gear reducer mechanism.

Limit switches M0 and 141 are provided for confining the movement of the arm 129 to a safe range.

It is seen that adjusting motor 137 for the articulation timing means will be driven at the same time and by the same master control as the adjusting motor 134 for the main drive motor, hence as the press speed is increased the signals means 12%) and 121 will be advanced relative to the turned position of the rolls to provide sufficient time for the articulating power means to act to cause the rolls to register at the proper circumferentially turned posi* tions when articulated.

It is thus seen that the invention provides improved means and method for printing cross borders on webs in a large range of selective lengths and for controlling the articulation stroke to obtain shorter and faster movement with less impact and damage whereby shorter length at greater roll speeds can be printed with great accuracy of registration; also that the controls provide immediate restoration to normal printing where the rolls are articulated through a greater range for printing and idling conditions; also that means and method are provided for adjusting the articulation signal control timing in coordination with the speed control of the press.

It will be understood that the drive for the signal timing disk 118 may be taken from any of the rolls of the set. It is shown as being taken from the offset roll by a chain and sprocket arrangement.

Balancing resistance or inductance circuits or other known means may be used to secure the proper directional and proportional operation of the subservient speed control and articulation control motors 13-4 and 137 respectively.

While one embodiment of the invention has been disclosed for purposes of illustration it is to be understood that there may be various embodiments and modifications within the general scope of the invention.

We claim:

1. Apparatus for articulating printing rolls for varying roll speeds, as for skip printing rug cross borders on a travelling web, comprising in combination: a roll stand having a set of cooperating rolls, including an engraved roll, an impression roll with the web to be imprinted passing thereover, and an offset roll mounted to be articulated from and toward said engraved and impression rolls while turning in continued coordination therewith; and articulating means for moving said offset roll from and toward said engraved and impression rolls; said articulating means including, for each end of the ofifsct roll, a cradle pivoted at two points adjacent the nips between the offset roll and the engraved roll and impression roll respectively, and supporting the otfset roll between said two pivot points; separate independently controllable power motor means for selectively moving either end of the cradle about the pivot at the other end to separate the offset roll at either nip selectively; and control means for said power motor means operated coordinately with the turning of said rol-ls for either placing the offset roll in engagement with both the engraved and impression rolls, or separating it from both rolls, or selectively separating it from either roll; means including a member operated with and at the same speed as said rolls, for timing the movement of said articulating power means; and means responsive to the speed of the rolls for varying the action of said timing means in accordance with changes in speed of the rolls.

2. Apparatus as set forth in claim 1, in which the timing means includes a separate timing control for the power means at each end of the cradle.

3. Apparatus as set forth in claim 1, in which the timing means includes a separate timing control for the power means at each end of the cradle, and in which said means for varying the action in accordance with roll speed comprises a unit control means arranged to change the timing of the power means for both ends of the cradle together.

4. Apparatus for articulating printing rolls of varying speeds, as for skip printing ru-g cross borders on a travelling web, comprising in combination: a set of printing rolls including an engraved roll, an impression roll, and an oifset roll rotatable in unison with the engraved and impression rolls and mounted for articulation relative to the engraved and impression rolls; articulating power means having a relatively constant actuating time for moving said offset roll relative to said engraved roll for receiving an inked impression and for moving the offset roll relative to the impression roll to print on the web supported thereon; means including a member operated with and at the same speed as said rolls for timing the movement of said articulating power means; and means responsive to the speed of the rolls for automatically varying the precise moment of action of said timing means in accordance with changes in speed of the rolls, said member operated with said rolls having circumferentially spaced impulse transmitting elements, signal impulse input-output means positioned for transmitting and receiving signal impulses with the passage of said signal transmitting elements, and means for varying the relative circumferential position of said input-output means so as to affect the moment of signal relative to the rotational position of the signal transmitting elements, and consequently the relative rotational position of the offset cylinder in accordance with the speed changes in rotation of said oifset cylinder.

5. Apparatus for periodically articulating one roll of a set which rotates in unison; comprising in combination: main power means for driving the rolls, articulating power means for articulating said one roll, said articulating power means having a substantially fixed time period for articulating said one roll; speed control means for the main power driving means of the set of rolls; and interconnected means controlled conjointly with said speed control means which advances the time of action of said articulating power means with increase in the speed of the rolls, or conversely which retards the time of action of articulating power means with reduction in speed of the rolls, said interconnected means including a rotary signal timing device connected to rotate in unison with said rolls; a signal producing device operated by said signal timing device and mounted for circumferential adjiustment relative thereto; and an auxiliary power device actuated from said speed control means for shifting said signal producing means relative to said rolls.

6. Apparatus for periodically articulating one roll of a set which rotates in unison; comprising in combination: main power means for driving the rolls, articulating power means for articulating said one roll, said articulating power means having a substantially fixed time period for articulating said one roll; speed control means for the main power driving means of the set of rolls; and interconnected means controlled conjointly with said speed control means which advances the time of action of said articulating power means with increase in the speed of the rolls, or conversely which retards the time of action of articulating power means with reduction in speed of the rolls, said interconnected means including a rotary signal timing device connected to rotate in unison with said rolls; a signal producing device operated by said signal timing device and mounted for circumferential adjustment relative thereto; and an auxiliary power device actuated from said speed control means for shifting said signal producing means relative to said rolls, said signal timing means including a rotary disk connected to turn in unison with said rolls and having circumferentially spaced signal timing elements; and said signal producing means includes a supporting part having an arm turnable about the axis of said disk; an operating arm controlled and turned in response to roll speed adjustments; and an adjustable link pivotally secured between said arms for changing the ratio of movement therebetween.

References Cited by the Examiner UNITED STATES PATENTS 2,356,058 8/1944 Hunting 10l144 2,362,736 11/1944 Weiss 10l247 X 2,893,310 7/1959 Johnson 101 182 2,950,674 8/1960 Taylor et al 101--218 2,967,475 1/1961 Ritzerfeld et al. 10l144 X 3,007,404 11/1961 Crawford et al. 10l181 X 3,030,884 4/1962 Lindeman-n 10l2l8 3,146,705 9/1964 Ritzerfeld et al. 10l144 ROBERT E. PULFREY, Primary Examiner.

EUGENE R. CAJPOZIO, Examiner. 

1. APPARATUS FOR ARTICULATING PRINTING ROLLS FOR VARYING ROLL SPEEDS, AS FOR SKIP PRINTING RUG CROSS BORDERS ON A TRAVELLING WEB, COMPRISING IN COMBINATION: A ROLL STAND HAVING A SET OF COOPERATING ROLLS, INCLUDING AN ENGRAVED ROLL, AN IMPRESSION ROLL WITH THE WEB TO BE IMPRINTED PASSING THEREOVER, AND AN OFFSET ROLL MOUNTED TO BE ARTICULATED FROM AND TOWARD SAID ENGRAVED AND IMPRESSIONS ROLLS WHILE TURNING IN CONTINUED COORDINATION THEREWITH; AND ARTICULATING MEANS FOR MOVING SAID OFFSET ROLL FROM AND TOWARD SAID ENGRAVED AND IMPRESSION ROLLS; SAID ARTICULATING MEANS INCLUDING, FOR EACH END OF THE OFFSET ROLL, A CRADLE PIVOTED AT TWO POINTS ADJACENT THE NIPS BETWEEN THE OFFSET ROLL AND THE ENGRAVED ROLL AND IMPRESSION ROLL RESPECTIVELY, AND SUPPORTING THE OFFSET ROLL BETWEEN SAID TWO PIVOT POINTS; SEPARATE INDEPENDENTLY CONTROLLABLE POWER MOTOR MEANS FOR SELECTIVELY MOVING EITHER END OF THE CRADLE ABOUT THE PIVOT AT THE OTHER END TO SEPARATE THE OFFSET ROLL AT EITHER NIP SELECTIVELY; AND CONTROL MEANS FOR SAID POWER MOTOR MEANS OPERATED COORDINATELY WITH THE TURNING OF SAID ROLLS FOR EITHER PLACING THE OFFSET ROLL IN ENGAGEMENT WITH BOTH THE ENGRAVED AND IMPRESSION ROLLS, OR SEPARATING IT FROM BOTH ROLLS, OR SELECTIVELY SEPARATING IT FROM EITHER ROLL; MEANS INCLUDING A MEMBER OPERATED WITH AND AT THE SAME SPEED AS SAID ROLLS, FOR TIMING THE MOVEMENT OF SAID ARTICULATING POWER MEANS; AND MEANS RESPONSIVE TO THE SPEED OF THE ROLLS FOR VARYING THE ACTION OF SAID TIMING MEANS IN ACCORDANCE WITH CHANGES IN SPEED OF THE ROLLS. 